In recent years, liquid crystal display panels are widely used. Further, developments are made so as to achieve practical use of organic electroluminescence (EL) display panels. These display panels are often active-matrix display panels in which each pixel is driven and controlled by a TFT each formed below a light-emitting unit (Patent Literature 1, 2, and 3). As an example, the following describes an overview of a method of manufacturing an organic EL display panel, with reference to FIG. 14.
A TFT layer is formed on an upper surface of a substrate 900, as illustrated in FIG. 14. The TFT layer has a gate electrode 901, a gate insulating layer 902, a channel layer 903, a channel protection layer 904, a source electrode 905 and a drain electrode 906, an interlayer electrically-insulating layer 907, an upper electrode 908, and a passivation layer 909 that are formed in this order from a side of the TFT layer of the substrate 900.
Next, an organic light-emitting unit (display element unit) is formed above the passivation layer 909 of the TFT layer with a planarizing layer 910 disposed between the organic light-emitting unit and the passivation layer 909. The organic light-emitting unit has an anode 911, banks 912, an organic light-emitting functional layer 913, a cathode 914, and a sealing layer 915 that are disposed in this order from a light-emitting unit side of the passivation layer 909.
Next, a color filter substrate (CF substrate) is formed above the organic light-emitting unit with a resin layer 916 disposed between the CF substrate and the organic light-emitting element. The CF substrate has a color filter layer 917 and a black matrix layer 918 that are formed on a lower surface of a substrate 919.
The upper electrode 908 of the TFT layer is electrically connected to the source electrode 905. The upper electrode 908 is also electrically connected to the anode 911 through contact holes formed in the passivation layer 909 and the planarizing layer 910. The contact holes are formed through the following processes: forming a contact hole in the planarizing layer 910 through lithography; and forming a contact hole in the passivation layer 909 through dry-etching the passivation layer 909 by using the planarizing layer 910, in which a contact hole has been formed, as a mask. The contact hole in the passivation layer 909 connects to the contact hole in the planarizing layer 910.